Hot-air furnace construction



July 24, 1951 c. E. OLSEN 2,561,479

HOT AIR FURNACE CONSTRUCTION Filed Sept. 27. 1948 2 Sheets-Sheet l July24, 1951 OLSEN 2,561,479

HOT AIR FURNACE CONSTRUCTION Filed Sept. 27, 1948 2 Sheets-$heet 2jazz/Zia CWazae 5,1949%? Patented July 24, 1951 UN! TED STATE S PATENTOFFICE 2,561,479 HOT-AIR FURNACE CONSTRUCTION ClarenceE. Olsen,Minneapolis, Minn.

Applicationfseptember 27, 1948:, Serial No. 51438-1 it Claims. (Q1.126-406).

Referring to the accompanying drawings, wherein like characters indicatelike parts throughout the several views:

Fig. 1 is a front elevation of my novel furnace, some parts being brokenaway and some parts shown in section; and

Fig. 2 is a vertical section taken substantially on the line 2--2 ofFig.1.

Referring with greater particularity to the drawings, the numeral Iindicates in its entirety anexternal casing or jacket: comprising frontand back walls 2 and 3 respectively, sidewalls 4, and a top wall. 5..Extending between the front and rear walls 2 and 3 respectively are apair of upstanding flanges 6 which are spaced from each other and fromthe side walls 4 and which define the side walls of a fire box I and anash pit 8 which are separated by a conventional grate structure 9. Firebox I and ash pit 8 are accessible through doors I and II respectivelysecured on a supplementary front wall element or plate I2.

Spaced inwardly from the side walls 4 and top wall 5 and extendingbetween front and rear walls 2 and 3 respectively is an inverted U-shaped baflle I3. Preferably and as shown, the jacket I extends to thefloor; whereas, the lower ends of the bafile I3 are spaced from thefloor but are inturned as indicated at I4 to make sealing connectionwith opposite sides of the opposite flanges 6, as indicated at I5.Itwill be noted that the connections I5 of the baffle I3, to the flanges6, are preferably below the lower limits of the fire box. The side walls4 of the jacket, a portion of the front and rear Walls 2 and 3, and thetop wall 5 define the outer wall of a heating chamber, indicated by thenumeral I 6; whereas, the bafile I3 defines the inner wall of saidchamber.

Also extending between front and rear walls 2 and 3 in spaced relationto baflle I3 is an inverted generally U-shaped tubular member I1,

2. which straddles the fire box I with the legs I8 thereof being inspaced relation to the baffle t3, the lower end portions. I4 thereof,and the flanges 6. The space intermediate the fire box I and the innerwall I9 of the tubular element I'I defines a combustion chamber A. Itwill be observed that the inner wall I9 of said-v tubular element I1guides and deflects the gases of combustion outwardly and downwardlythrough. the

passage to a point below the fire box 1. It, will also be observed thatthe outer wall 2! of the tubular member I? forms the inner wall of asmoke passage 22 formed therebetween and the inner wall of the baffleI3. An outlet 23. connects the passage 2'2 to a smoke stack, not shown.

The tubular element I1 is in reality a heating chamber. In fact, it isthe heating chamber I, from which the greatest amount of heat. isderived. Referring particularly to Fig. 2, it will be observed that thetubular element or heating chamber I1 is connected at its opposite endsto suitable conduits 24 through the medium of segmental headers 25'.

Also preferably and as shown, I provide a transverse tubular element 26which projects through the upper portion of opposite legs I8 ofthejtubular element I1 and through the upper most portion of thecombustion chamber A.

The tube 26 is provided at its central portion with a damper 21 whichmay be opened to permit direct communication between the combustionchamber A and the opposite sides of the smoke passage 22. Thisarrangement is for precautionary purposes, and satisfies laws present incertain communities prohibiting pockets for the accumulation of gas. Itshould be obvious that when the damper 21 is opened to any extent, gasesaccumulating in the combustion chamber A will be allowed to escapethrough the tube 26 to the smoke passage 22.

When it is desired to use my novel furnace in a forced air system, thewarm air is drawn off from the chamber I! through one of the ducts 24,as indicated by arrows in Fig. 2, and is returned through the otherthereof. It will be noted that the air within said chamber I1 is heatedby the gases of combustion in their travel upwardly into the combustionchamber A, downwardly against the inner wall I 9 through passage 20, andupwardly through the smoke passage 22 and through the outlet 23 to thechimney, not shown. To fully recover the heat which is transferred tothe baffle I3 in its travel upwardly through the smoke passage 22, Iprovide a suitmanipulation and adjustment of the damper 21 through anaperture 32 in the front wall 2.

I provide suitable clean-out openings 33 and 34 in the front wall 2 forcommunication with the top and bottom portions respectively of the smokepassage 22. Openings 33 and 34 are normally closed by plugs 35. With theplugs 35 re- 1 moved from the openings 33 and 34, the interior of thesmoke passage may be cleaned by a conventional suction furnace cleaner.

If desired, a pair of ducts 36 may be provided which extend from thewall 2i to the upper portion of the'baiile l3 and form passages 31communicating with the heating chamber l6 and the tubular element ll.This arrangement permits a thorough mixing of air so that air of uniformtemperature is delivered to all outlets.

My invention has been thoroughly tested and found to be entirelyadequate for the accomplish:

ment of the above objects; and, while I have shown a preferredembodiment of the invention, it will be'understood that the same iscapable of modification without departure from the scope and spirit ofthe invention as defined in the claims.

What I claim is:

1..In a device of the class described, a jacket including front. andrear walls, side walls, and top wall, said jacket defining the outerwalls of a heating chamber having air inlet and outlet means, a pair oilaterally-spaced upstanding flanges. extending between said front andback walls, said flanges being spaced from the side walls of the jacketand defining a fire box .in the lower portion of said jacket, aninverted U- shaped baffle extending between the front, and back walls ofsaid jacket, said U-shaped baflie at its upper end being spaced, fromthe top wall of saidheating chamber and having its lower. endsprojecting downwardly below the upper edges of,

said ,fire box forming fianges, one each of said lower endsof the bafilebeing disposed intermee '4 diate one of the outer walls of said jacketand the adjacent of said fire box-forming flanges, means associated withthe lower ends of said baffle preventing communication between the firebox and said heating chamber, an inverted cross-sectionally U -shapedtubular member extending between the front and rear walls of said jacketand de? fining a second heating chamber, said tubular member beingspaced from said baffle and having its lower ends projecting below theupper edges of the fire box-forming flanges in outwardlyspaced relationto said fianges and terminatin in upwardly-spaced relation to the lowerends of said bafile, the intermediate portion of said tubular member andsaid flanges defining the top and side wall of'a combustion chamber, airinlet and outlet means for said tubular member, said fire box-formingflanges tubular member and baiile defining side walls of a smokepassage, said tubular member deflecting the gases of combustiondownwardly and outwardly below the upper edges of said flanges, andoutlet means from said smoke passage.

2. The structure defined in claim 1 in further combination with a gratestructure defining the lower limits of said fire box and in which thelower ends of said U-shaped baffie are secured to opposite side walls ofsaid fire box below the level of said grate structure.

3. The structure defined in claim 1 in which said tubular member iscross sectionally crescent shape. I

4. The structure defined in claim 1 in further combination with atransversely-extended tube connecting opposite sides of said smokepassage,

said tube extending through the upper portion of the legs of saidtubular member and through said combustion chamber and being provided,in: termediate its ends, with a damper communicating with saidcombustion chamber.

CLARENCE E. OLSEN.

, REFERENCES CITED The following references are of record in the file ofthis patent: v

UNITED STATES PATENTS 7 Number Name .Date v 616,844 Howard Dec. 27,18931,491,191 Bruder Apr. 22, 1924. 2,408,087 Miles Sept. 24, .1946

2,408,991 Mumma Oct. 8,1946,

